Shell reamer



Sept. 30, 1930. J. G. MATTHEWS SHELL REAMER Filed March 21, 1929 INVENTOR flf T/Ok/Y 6. d/ffi J BY "6% 55,1

' ATTORNEY 5 Patented Sept. 30, 1930 PATENT OFFICE JOHN G. MATTHEWS, OF BEBEA, OHIO SHELL REAMER Application filed March 21, 1929. Serial No. 348,839.

The main objects of this invention are: First, to provide an improved adjusting means whereby the sizes of a shell reamer can be restored after wear or grinding.

Second, to provide such an adjusting means that will maintain the size of the shell reamer to the endot the tool for end cutting. Objects pertaining to details and economies of construction and operation will definitely appear from the description to follow. A

"preferred embodiment of my invention is clearly V illustrated in the accompanying drawing, 1n which:

s Fig. 11s a side elevation of myimproved 'reamer and end cutter, the end cutter on this reamerbemg for a special use.

Fig. 2 is a longitudinal sectlonal view on the irregular longitudinal section indicated by line 2-2 in Figs. 1, 3 and 4.

Fig. 3 is a cross section on line 33 of Figs. 1 and showing a pair of the driving keys for the segments.

Fig. 1 is a cross section on line 4-4 of Figs. 1 and 2 showing the plurality of splines for securing the reamer to the boring bar.

Fig. 5 is a modified form of my reamer, the guide and the end cutter being eliminated.

The parts will be identified by their numerals of reference which are the same in all the views.

1 is the boring bar comprising the shank 11, a conical portion 12, a threaded portion 13 and a guide shank 14 threaded at 15 and splined to drive the reamer. 2 is the eX- panding reamer shell having radial kerfs 21 cut therein, which form the plurality of expansible segments 22 each carrying a pair of the reamer blades 23 secured thereto by brazing or otherwise and adapted to cut at their ends as well. The reamer segments are beveled around the central bore to receive the cone 12 for expanding the same. The reamer shell 2 is forced onto the cone by the screw nut 26 which forces the shell outwardly and expands the cutters on the cone.

A set of keys 24, one for each kert 21, forms the splines for driving the segments. The keys retain the reamer body on the carrying bar. 3 is the end cutter having a plurality of blades 31 and is secured to the boring bar by the clamping nut 32. IneX- panding the reamer the nut 32 is loosened and the nut 26 tightened until the reamer is expanded. The nut 32 is then tightened up, which retains the end cutter in place and serves to lock theparts.

In Fig. 5 my improved reamer has been modified by the entire elimination of the end cutter 31 and of the guide 1& and the clamping nut for the end cutter. The ends 231 of the cutter blades 23 have been formed into end cutters and because they projectbeyond the end of the boring bar permit the boring of holes to the bottom and thus finishing the same. The elasticity of the shell of the reamer is sufiicient to maintain the same in place.

A consideration of my improved structure 'will show that as a boring instrument the expand-the cutting end to take care of the wear. It is possible then by simply honing the cutter to proceed withthe boring job.

Again, it is desirable to adjust the tool for a variation in size of a fraction of a thousandth of an inch,- for instance in boring seats for ball bearing casings. This is possible to be done to secure a perfectly tight fi in a variation of a thousandth of an inch for smaller size bearings and from two to three thousandths of an inch on the larger sizes. The adjustments suggested are the extremes of what is necessary. This can bestbe done by simply expanding the end of the reamer cutter, when it is unnecessary to grind the whole length of the cutter blade.

From this it appears that my structure is capableof considerable modification. It is adapted for use with an end cutter which may be clamped thereto or the side cutting blades may-be extendedeven beyond the end 'pointed out in the appended claims,

of the boring bar and their ends be adapted kerfed at its outer end dividing it into expanto end cutting. it i sible segments, cutter blades with end and side I desire to claim the structure in the specutting edges secured on said segments procifio forms in which I have it illustrated and vided with end cutting portions, an adjusting also desire to claim the same broadly as nut back ofthe said reamer shell for expanding the same, and means coupling said shell to Having thus described my invention, what the boring bar.

I c aim new and desire to secure by Letters Patent, is t 6. In a shell reamer, the combination with a boring bar suitably threaded and provided 1. In a shell reamer, the combination with with a reverse conical portion adapted to ex 7 structure.

a splined: boring bar suitably threaded and panda the reamerand with a shoulder threadprovided with a reverse conical portion ed guide extension, a reamer shell with bore adapted to expand the reamer; and with a beveled for expanding and kerfed at its outer shouldered threaded guide extension, a end ,dividingit into expansible segments, an splined reamer shell withborebeveled for exadjusting nut back of the said reamer shell paneling and kerfeclv at its outer end dividing for expanding the same, and a ring end cutter itintoiexpansible segments, cutter bladeson with-projecting blades and clamp nut for saidsegments, an adjusting nut back of the clamping the same to the end of the said reamsaid reamenshell for expanding the sanae, er structure. keys on the said shaft engaging the kerfs be 7. In a shell reamer, the combination with tween: the expansible segments and keys to a splined boring bar suitably threaded and engage said splines, a ring end cutter with provided with reverse conical portion adaptprojecting blades and a clamp nut for clampedto expand the reamer at the cutting end, ing the same to theend of the said reamer of areamer shell with bore beveled for ex- 7 'panding and kerfed at its onterzlend dividing 1 2. In a shell reamer, the combination with it into end expansible segments, cutter blades 1 splined boring bar suitably threaded and Secured to said segments, an adjustingnut provided; with a reverse conical portion back of the said reamer shell for adjusting .ldaptedto expand theire'amer'at the cutting the bar to expand the ends of the said shell,

and, a splincd reamer shell with bore beveled and keys in the splines of the said shaft engag- -forexpending andkerfed; at its outer end diing he k r e een the expansible segviding it into I expansible segments, cutter m nts.

blades secured on said segments, an adjusting In witness whereof I have hereunto set, my nut back of the saidreamer shell for expandhanding'thesam andkeys onthesaidshaft en- J C=HN G. MATTHEWS. gaging the kerfs between the expansible segments and keys to engage said splines.

e 8. In. a shell reamer, thecembination with a splined boring bar suitably threaded and provided with a reverse conical portion adapted to expandthe reamer at the cutting end, a splined reamer shell with bore beveled for expandingand kerfed at its outer end dividing it into expansible segments, cutter blades secured on :saidsegments, an adjusting nut "back ofthe said reamer shell for expanding the same, and keysion the said shaft engaging the'kerfs between the expansible segments.

4. In a shell reamer, the combination with aboring bar suitably threaded and provided with a reverse conical portion adapted to expandrithe reamer at the cutting endfa reamer shell with borebeveled for expanding and kerfedzat its outerend dividing it into expansible segments,cutter blades secured on said segments, and an adjusting nut'back of the said reamer shell for "expanding the same, grad means conpiing said shell to the boring a1. i

5. ,In ashell reamer, the combination-with a boring bar suitably v threaded and provided with a, reverse conical portion. adapted to expand the. reamer atthe cutting end, a, reamer M sh ll; with bore be eled ,for expanding n 

